Insect Pests of Vegetable, Tuber and Spice Crops

Red cotton bug

6. Red cotton bug, Dysdercus koenigii (Pyrrhocoridae: Hemiptera)

Damage

• Adults as well as nymphs suck the cell sap from plants
• Hibiscus rosa sinensis is the most preferred
• Plants loose their vitality and flower bearing capacity.

Life cycle and management of this pest has been described under the insect pest of okra

7. Cotton whitefly, Bemisia tabaci (Aleyrodidae: Hemiptera)

Hosts: Among ornamentals, it feeds on Euphorbia pulcherima, Dombeya spectalis, Poinciana pulcherima

Damage

• Both adults and nymphs suck the cell sap
• Down ward cupping of the leaves
• Nymphs excrete honeydew on which sooty mould develops
• Blackish look to the plants especially leaves. Excessive sap sucking result in premature leaf fall.

8. Jasmine thrips, Thrips orientalis (Thripidae: Thysanoptera)

Damage:

• The dark coloured jasmine thrips is mainly found on Jasminum maltiflorum from February to April
• Both adults and nymphs feed on flower by rasping the petals and feed on the oozing cell sap
• Attacked flowers give a decayed look and fall off prematurely.

Management

• Same as discussed under rose.

9. Lilly moth, Polytela gloriosae (Noctuidae: Lepidoptera)

Distribution: Sporadic and specific pest of lilies in India and Sri Lanka.

Identification

• The larvae have chocolate brown head
• They defoliate the lily plants
• The full grown larva measures 39-42 mm and possesses black, white and red mosaic pattern on the body
• The moth has mosaic pattern of red, yellow and black on fore wings with a row of black and yellow dots on the apical margins
• The hind wings are black.

Life cycle:

• Lays round eggs on the apical portion of the under surface of leaves in clusters of 13-42 eggs
• Larvae emerge from eggs after 3-6 days
• Feed on leaves for 16-20 days
• Adults emerge within 15-20 days

Salient features

• Adults moths emerge from the diapausing pupae after the first heavy shower during July
• Pupate in the soil in earthen cocoons
• The insect has two generations in a year
• Pupae of second generation hibernate